1 DIAMOND OFFSHORE DRILLING, INC. ("COMPANY") DEBT SECURITIES TERMS AGREEMENT January 29, 1997 To: The Underwriters identified herein Dear Sirs: The undersigned agrees to sell to the several Underwriters named in Schedule A hereto for their respective accounts, on and subject to the terms and conditions of the Underwriting Agreement incorporated by reference in the Company's registration statement on Form S-3 (No. 333-19987) ("Underwriting Agreement"), the following securities ("Offered Securities") on the following terms: TITLE: 3 3/4% Convertible Subordinated Notes Due 2007. PRINCIPAL AMOUNT OF FIRM SECURITIES: $350,000,000. PRINCIPAL AMOUNT OF OPTIONAL SECURITIES: $50,000,000. TERM OF OVER-ALLOTMENT OPTION: 30 days from the date of this agreement. INTEREST: 3 3/4% per annum, from February 4, 1997 , payable semiannually on February 15 and August 15 of each year, commencing August 15, 1997, to holders of record on the preceding February 1 or August 1, as the case may be. MATURITY: February 15, 2007. OPTIONAL REDEMPTION: The Notes may be redeemed at the option of the Company, at any time and from time to time, in whole or in part, on at least 30 and not more than 60 days' notice by mail to the registered Holders thereof, at any time on or after February 22, 2001 and prior to February 15, 2002 at 102.08% of principal amount and, thereafter, at the following redemption prices (expressed as percentages of principal amount), if redeemed during the 12-month period beginning on February 15 of the years set forth below: YEAR PERCENTAGE ---- ---------- 2002 . . . . . . . . . . . . . 101.67% 2003 . . . . . . . . . . . . . 101.25% 2004 . . . . . . . . . . . . . 100.83% 2005 . . . . . . . . . . . . . 100.42% and thereafter at 100% of the principal amount thereof; in each case together with accrued and unpaid interest to (but not including) the redemption date (subject to the rights of holders on any regular record date to receive interest due on any interest payment date that is on or prior to such redemption date). 2 SINKING FUND: None. LISTING: None. DELAYED DELIVERY CONTRACTS: None. PURCHASE PRICE: 98.75 % of principal amount, plus accrued interest, if any, from February 4, 1997. CONVERSION PRICE: The Notes are convertible into shares of Common Stock of the Company, par value $0.01 per share, at a conversion price of $81.00 per share (equivalent to a conversion rate of 12.346 shares per $1,000 principal amount of Notes), subject to adjustment in certain circumstances. EXPECTED REOFFERING PRICE: 100.0% of principal amount, subject to change by the Underwriters. CLOSING: 9:00 A.M. on February 4, 1997, at the offices of Andrews & Kurth L.L.P., 425 Lexington Avenue, 10th Floor, New York, New York 10017, in Federal (same day) funds. SETTLEMENT AND TRADING: Book-Entry Only via DTC. The Offered Securities will trade in DTC's Same Day Funds Settlement System. BLACKOUT: Until 90 days after the First Closing Date. NAME AND ADDRESS OF REPRESENTATIVE: Credit Suissee First Boston Corporation, 11 Madison Avenue, New York, New York 10010-3629 The respective principal amounts of the Offered Securities to be purchased by each of the Underwriters are set forth opposite their names in Schedule A hereto. The provisions of the Underwriting Agreement are incorporated herein by reference. The Offered Securities will be made available for checking and packing at the office of the Trustee at least 24 hours prior to the Closing Date. For purposes of Section 6 of the Underwriting Agreement, the only information furnished to the Company by any Underwriter for use in the Prospectus consists of (i) the following information in the Prospectus furnished on behalf of each Underwriter: the last paragraph at the bottom of the prospectus supplement cover page concerning the terms of the offering by the Underwriters, the legend concerning over-allotments and stabilizing on the inside front cover page of the prospectus supplement, the concession and reallowance figures appearing in the fourth paragraph under the caption "Underwriting" in the prospectus supplement and (ii) the following information in the prospectus supplement furnished on behalf of Merrill Lynch & Co., Merrill Lynch, Pierce Fenner & Smith Incorporated: the third legend on the inside front cover page and the last paragraph under the caption "Underwriting" concerning Merrill Lynch Specialists Inc. acting as a specialist. 2 3 If the foregoing is in accordance with your understanding of our agreement, kindly sign and return to the Company one of the counterparts hereof, whereupon it will become a binding agreement between the Company and the several Underwriters in accordance with its terms. Yours very truly, DIAMOND OFFSHORE DRILLING, INC. By /s/ Robert E. Rose -------------------- Name: Robert E. Rose Title: President and Chief Executive Officer The foregoing Terms Agreement is hereby confirmed and accepted as of the date first above written. CREDIT SUISSE FIRST BOSTON CORPORATION By /s/Rome Arnold --------------------- Name: Rome Arnold Title: Managing Director Acting on behalf of itself and as the Representative of the several Underwriters. 3 4 SCHEDULE A PRINCIPAL UNDERWRITER AMOUNT ----------- ------ Credit Suisse First Boston Corporation . . . . . . . . . . . . . . . . . $116,668,000 Merrill Lynch, Pierce, Fenner & Smith Incorporated . . . . . . . . . . . $116,666,000 Salomon Brothers Inc . . . . . . . . . . . . . . . . . . . . . . . . . . $116,666,000 ------------ Total. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . $350,000,000 ============ 4 5 ANNEX I LIST OF SUBSIDIARIES INCORPORATION SUBSIDIARY STATE/COUNTRY - ---------- ------------- Diamond Offshore Company De Diamond Offshore General Company De Diamond Offshore Guardian Company De Diamond Offshore Southern Company De Diamond Offshore Management Company De Diamond Offshore (USA) Inc. De Diamond Offshore Alaska, Inc. De Diamond Offshore Atlantic, Inc. De Diamond Offshore (Mexico) Company De Diamond Offshore Drilling Services, Inc. De Diamond Offshore International Corporation De Diamond Offshore Enterprises, Inc. De Cumberland Maritime Corporation De Diamond Offshore Turnkey Services, Inc. De Diamond Offshore Finance Company De Diamond Offshore Perforadora, Inc. De Diamond Offshore Limited England Diamond Offshore Drilling (UK), Limited England Diamond Offshore Development Company De Diamond Offshore (Indonesia) Inc. De Diamond Offshore Drilling (Overseas) Inc. De Diamond Offshore Exploration (Bermuda) Limited De Arethusa Off-Shore Company De Concord Drilling Limited De Saratoga Drilling Limited De Yorktown Drilling Limited De Scotian Drilling Limited De Heritage Drilling Limited De Sovereign Drilling Limited De Miss Kitty Drilling Limited De Neptune Drilling Limited De Whittington Drilling Limited De Yatzy Drilling Limited De Winner Drilling Limited De Lexington Drilling Limited De 5